Look, we are all verbally abusive at times IMHO. However, if you are able to say I am sorry and mean it and, hopefully, not repeat the abuse (telling you W 'she is wrong', 'you don't mean that', calling names etc), you are not abusive. Abuse is systematic covert or over but constant. If your W struggles to, or never, apologises then she is most likely abusive and sadly she may never change. The book I pointed you towards is Patricia Evan's. Learn to cope with her for now, strengthen yourself and DO NOT ENGAGE.
I am so sorry you are going through this. It's not your fault. In many ways it's not hers either. Someone else damaged that little girl in your W. Try and be as kind and sympathetic as you can but do not get on the crazy train.
If it helps, you are not alone. I have lived this and a, still living this, it gets better but it's not yet amazing. It will be however, for I control my own happiness. You control yours too....
Just be as strong as you can be for your D and SS and don't expose them to any animosity at all if you can.
Surfer.
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